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Showing posts from January, 2017

Three sums of electrical power have been discussed in this video. This is the second part of sum discussion . Sum 1: A water heater has a rating of 4 KVA , 240 V.
a) What is the electrical energy consumed by it in:
i)KWhr and
ii) in Joul.
if it is used for 180 minutes.
b) Find the cost of electricity if the rate is
Rs. 7.00 per commercial unit.
+ Solution 1 - Close Solution 1 Sum 2: The water in an electric kettle took 5 minutes to reach its boiling point when it is connected to 220 v supply.
How long would it have taken if the supply voltage had fallen to 200 v. + Solution 2 - Close Solution 2 Sum 3: What is the resistance under normal working conditions of 240V electric lamp rated at 60 W ? If two such lamps are connected in series across a 240 mains supply, explain why each one appears less bright. + Solution 3 - Close Solution 3

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Ratio Mathematics ICSE Tutorial Class 7

There are four videos of Ratio class 7. Few sums have also been explained with very easy steps. If there are any doubts then comment below. We will try to clear those doubts.

1. Understanding Ratio:


2. Comparing Ratio Basic and Shortcut method:

3. Compound Ratio , continued Ratio Dividing a number in a given Ratio:

4. Solution of few problem of ratio:
These sums of Ratio class 7 have been discussed in this video:
1. write in simplest form
72:108, 1/6:1/2,
15cm to 4m.
2. Population of a village is 32400. The ratio of literate
to illiterate person in the village is 11:7. Find the actual number of literate person and illiterate person. .
3. If a, b and c are three numbers such that a:b=4:9 and b:c=27:35. Find a:c
4. In what ratio should we increase 650 to obtain 1000.